Fractional CMO vs marketing agency: which one do you actually need?

What each one actually delivers

• Fractional CMO: strategy, positioning, pricing, channel selection, budget allocation, hiring and managing whoever executes. Typically 1–3 days a month of senior time. Does not produce the ads themselves.
• Marketing agency: execution capacity — campaigns, content, creative, landing pages, reporting. Follows a strategy; rarely sets the commercial one.
• In-house marketing manager: full context and availability, but usually one specialisation and a $90k+ fully loaded annual cost.

Real cost comparison

• Fractional CMO: $3,000–8,000/month, no ad budget included, cancellable quarterly.
• Full-service agency: $3,000–10,000/month retainer plus ad spend.
• Full-time CMO: $180,000–260,000/year plus equity — only sensible above roughly $5M in revenue.
• Hybrid (fractional CMO + specialist agency): $6,000–12,000/month, the most common setup for $1–5M businesses.

Choose a fractional CMO when

• You're running channels but can't say which one produces profitable customers.
• You have people or vendors executing, but nobody accountable for the number.
• Positioning and pricing haven't been revisited since launch.
• You're about to raise or scale spend and need a defensible plan first.

Choose an agency when

• You already know your channel and your offer converts — you need more output.
• You need specialist skills (paid media, SEO, video) you won't hire full-time.
• There's an internal owner who can brief and approve work.

The diagnostic question

Ask yourself: if I doubled my marketing output tomorrow, would revenue double? If yes, you have an execution gap — hire an agency. If you're not sure, or you suspect you'd just spend twice as much for the same result, you have a strategy gap — start with a fractional CMO, then add execution.